#include <fstream>
#include <iostream>

#include "boost/algorithm/string.hpp"

#include "gtest/gtest.h"

#include "json/json.h"

#include "webcc/client_session.h"
#include "webcc/fs.h"
#include "webcc/string.h"

// -----------------------------------------------------------------------------

// JSON helper functions (based on jsoncpp).

// Parse a string to JSON object.
static Json::Value StringToJson(const std::string& str) {
  Json::Value json;

  Json::CharReaderBuilder builder;
  std::istringstream stream{ str };
  std::string errors;
  if (!Json::parseFromStream(builder, stream, &json, &errors)) {
    std::cerr << errors << std::endl;
  }

  return json;
}

// -----------------------------------------------------------------------------

TEST(ClientTest, Head) {
  webcc::ClientSession session;

  try {
    auto r = session.Send(webcc::RequestBuilder{}.
                          Head("http://httpbin.org/get")
                          ());

    EXPECT_EQ(webcc::Status::kOK, r->status());
    EXPECT_EQ("OK", r->reason());

    EXPECT_TRUE(r->HasHeader(webcc::headers::kContentLength));

    // The response of HTTP HEAD method has no body.
    EXPECT_EQ("", r->data());

  } catch (const webcc::Error& error) {
    std::cerr << error << std::endl;
  }
}

// -----------------------------------------------------------------------------

TEST(ClientTest, Get) {
  webcc::ClientSession session;

  try {
    auto r = session.Send(webcc::RequestBuilder{}.
                          Get("http://httpbin.org/get").
                          Query("key1", "value1").Query("key2", "value2").
                          Header("Accept", "application/json")
                          ());

    EXPECT_EQ(webcc::Status::kOK, r->status());
    EXPECT_EQ("OK", r->reason());

    Json::Value json = StringToJson(r->data());

    Json::Value args = json["args"];

    EXPECT_EQ(2, args.size());
    EXPECT_EQ("value1", args["key1"].asString());
    EXPECT_EQ("value2", args["key2"].asString());

    Json::Value headers = json["headers"];

    EXPECT_EQ("application/json", headers["Accept"].asString());
    EXPECT_EQ("identity", headers["Accept-Encoding"].asString());
    EXPECT_EQ("httpbin.org", headers["Host"].asString());

  } catch (const webcc::Error& error) {
    std::cerr << error << std::endl;
  }
}

// Test the space in the query string could be encoded.
TEST(ClientTest, Get_QueryEncode) {
  webcc::ClientSession session;

  try {
    auto r = session.Send(webcc::RequestBuilder{}.Get("http://httpbin.org/get").
                          Query("name", "Chunting Gu", true)
                          ());

    EXPECT_EQ(webcc::Status::kOK, r->status());
    EXPECT_EQ("OK", r->reason());

    Json::Value json = StringToJson(r->data());

    Json::Value args = json["args"];

    EXPECT_EQ(1, args.size());
    EXPECT_EQ("Chunting Gu", args["name"].asString());

  } catch (const webcc::Error& error) {
    std::cerr << error << std::endl;
  }
}

#if WEBCC_ENABLE_SSL
TEST(ClientTest, Get_SSL) {
  webcc::ClientSession session;

  try {
    // HTTPS is auto-detected from the URL scheme.
    auto r = session.Send(webcc::RequestBuilder{}.
                          Get("https://httpbin.org/get").
                          Query("key1", "value1").Query("key2", "value2").
                          Accept("application/json")
                          ());

    EXPECT_EQ(webcc::Status::kOK, r->status());
    EXPECT_EQ("OK", r->reason());

    Json::Value json = StringToJson(r->data());

    Json::Value args = json["args"];

    EXPECT_EQ(2, args.size());
    EXPECT_EQ("value1", args["key1"].asString());
    EXPECT_EQ("value2", args["key2"].asString());

    Json::Value headers = json["headers"];

    EXPECT_EQ("application/json", headers["Accept"].asString());
    EXPECT_EQ("identity", headers["Accept-Encoding"].asString());
    EXPECT_EQ("httpbin.org", headers["Host"].asString());

  } catch (const webcc::Error& error) {
    std::cerr << error << std::endl;
  }
}
#endif  // WEBCC_ENABLE_SSL

// Get a JPEG image (without streaming).
TEST(ClientTest, Get_Jpeg_NoStream) {
  webcc::ClientSession session;

  try {
    auto r = session.Send(webcc::RequestBuilder{}.
                          Get("http://httpbin.org/image/jpeg")
                          ());

    // TODO: Verify the response is a valid JPEG image.
    //std::ofstream ofs(<path>, std::ios::binary);
    //ofs << r->data();

  } catch (const webcc::Error& error) {
    std::cerr << error << std::endl;
  }
}

TEST(ClientTest, Get_Jpeg_Stream) {
  webcc::ClientSession session;

  try {
    auto r = session.Send(webcc::RequestBuilder{}.
                          Get("http://httpbin.org/image/jpeg")
                          (), true);

    auto file_body = r->file_body();

    EXPECT_TRUE(!!file_body);

    EXPECT_TRUE(!file_body->path().empty());

    // Backup the path of the temp file.
    const webcc::fs::path ori_path = file_body->path();

    const webcc::fs::path new_path("./wolf.jpeg");

    bool moved = file_body->Move(new_path);
    EXPECT_TRUE(moved);
    EXPECT_TRUE(webcc::fs::exists(new_path));
    // The file in the original path should not exist any more.
    EXPECT_TRUE(!webcc::fs::exists(ori_path));

    // After move, the original path should be reset.
    EXPECT_TRUE(file_body->path().empty());

  } catch (const webcc::Error& error) {
    std::cerr << error << std::endl;
  }
}

// Test whether the streamed file will be deleted or not at the end if it's
// not moved to another path by the user.
TEST(ClientTest, Get_Jpeg_Stream_NoMove) {
  webcc::ClientSession session;

  try {
    webcc::fs::path ori_path;

    {
      auto r = session.Send(webcc::RequestBuilder{}.
                            Get("http://httpbin.org/image/jpeg")
                            (), true);

      auto file_body = r->file_body();

      EXPECT_TRUE(!!file_body);

      EXPECT_TRUE(!file_body->path().empty());

      // Backup the path of the temp file.
      ori_path = file_body->path();
    }

    // The temp file should be deleted.
    EXPECT_TRUE(!webcc::fs::exists(ori_path));

  } catch (const webcc::Error& error) {
    std::cerr << error << std::endl;
  }
}

// -----------------------------------------------------------------------------

#if WEBCC_ENABLE_GZIP

// Test Gzip compressed response.
TEST(ClientTest, Get_Gzip) {
  webcc::ClientSession session;
  session.AcceptGzip();

  try {
    auto r = session.Send(webcc::RequestBuilder{}.
                          Get("http://httpbin.org/gzip")
                          ());

    Json::Value json = StringToJson(r->data());

    EXPECT_EQ(true, json["gzipped"].asBool());

  } catch (const webcc::Error& error) {
    std::cerr << error << std::endl;
  }
}

// Test Deflate compressed response.
TEST(ClientTest, Get_Deflate) {
  webcc::ClientSession session;
  session.AcceptGzip();

  try {
    auto r = session.Send(webcc::RequestBuilder{}.
                          Get("http://httpbin.org/deflate")
                          ());

    Json::Value json = StringToJson(r->data());

    EXPECT_EQ(true, json["deflated"].asBool());

  } catch (const webcc::Error& error) {
    std::cerr << error << std::endl;
  }
}

#endif  // WEBCC_ENABLE_GZIP

// -----------------------------------------------------------------------------

TEST(ClientTest, Post) {
  webcc::ClientSession session;

  try {
    const std::string data = "{'name'='Adam', 'age'=20}";

    auto r = session.Send(webcc::RequestBuilder{}.
                          Post("http://httpbin.org/post").Body(data).Json()
                          ());

    EXPECT_EQ(webcc::Status::kOK, r->status());
    EXPECT_EQ("OK", r->reason());

    Json::Value json = StringToJson(r->data());

    EXPECT_EQ(data, json["data"].asString());

  } catch (const webcc::Error& error) {
    std::cerr << error << std::endl;
  }
}

static webcc::fs::path GenerateTempFile(const std::string& data) {
  try {
    webcc::fs::path path =
        webcc::fs::temp_directory_path() / webcc::RandomString(10);

    webcc::fs::ofstream ofs;
    ofs.open(path, std::ios::binary);
    if (ofs.fail()) {
      return webcc::fs::path{};
    }

    ofs << data;

    return path;

  } catch (const webcc::fs::filesystem_error&) {
    return webcc::fs::path{};
  }
}

TEST(ClientTest, Post_FileBody) {
  webcc::ClientSession session;

  const std::string data = "{'name'='Adam', 'age'=20}";

  auto path = GenerateTempFile(data);
  if (path.empty()) {
    return;
  }

  try {
    auto r = session.Send(webcc::RequestBuilder{}.
                          Post("http://httpbin.org/post").File(path)
                          ());

    EXPECT_EQ(webcc::Status::kOK, r->status());
    EXPECT_EQ("OK", r->reason());

    Json::Value json = StringToJson(r->data());

    EXPECT_EQ(data, json["data"].asString());

  } catch (const webcc::Error& error) {
    std::cerr << error << std::endl;
  }

  // Remove the temp file.
  webcc::fs::error_code ec;
  webcc::fs::remove(path, ec);
}

#if WEBCC_ENABLE_GZIP
TEST(ClientTest, Post_Gzip_SmallData) {
  webcc::ClientSession session;

  try {
    // This data is too small to be compressed.
    const std::string data = "{'name'='Adam', 'age'=20}";

    // This doesn't really compress the body!
    auto r = session.Send(webcc::RequestBuilder{}.
                          Post("http://httpbin.org/post").Body(data).Json().
                          Gzip()
                          ());

    //Json::Value json = StringToJson(r->data());

  } catch (const webcc::Error& error) {
    std::cerr << error << std::endl;
  }
}
#endif  // WEBCC_ENABLE_GZIP

#if (WEBCC_ENABLE_GZIP && WEBCC_ENABLE_SSL)
// NOTE: Most servers don't support compressed requests!
TEST(ClientTest, Post_Gzip) {
  webcc::ClientSession session;

  try {
    // Use Boost.org home page as the POST data.
    auto r1 = session.Send(webcc::RequestBuilder{}.
                           Get("https://www.boost.org/")
                           ());

    const std::string& data = r1->data();

    auto r2 = session.Send(webcc::RequestBuilder{}.
                           Post("http://httpbin.org/post").Body(data).Gzip()
                           ());

    EXPECT_EQ(webcc::Status::kOK, r2->status());
    EXPECT_EQ("OK", r2->reason());

  } catch (const webcc::Error& error) {
    std::cerr << error << std::endl;
  }
}
#endif  // (WEBCC_ENABLE_GZIP && WEBCC_ENABLE_SSL)

// -----------------------------------------------------------------------------

// Test persistent (keep-alive) connections.
//
// NOTE:
// Boost.org doesn't support persistent connection and always includes
// "Connection: Close" header in the response.
// Both Google and GitHub support persistent connection but they don't like
// to include "Connection: Keep-Alive" header in the responses.
// URLs:
//   "http://httpbin.org/get";
//   "https://www.boost.org/LICENSE_1_0.txt";
//   "https://www.google.com";
//   "https://api.github.com/events";
//
TEST(ClientTest, KeepAlive) {
  webcc::ClientSession session;

  const std::string url = "http://httpbin.org/get";

  try {
    // Keep-Alive by default.
    auto r = session.Send(webcc::RequestBuilder{}.Get(url)());

    EXPECT_TRUE(boost::iequals(r->GetHeader("Connection"), "Keep-Alive"));

    // Close by setting Connection header directly.
    r = session.Send(webcc::RequestBuilder{}.Get(url).
                     Header("Connection", "Close")
                     ());

    EXPECT_TRUE(boost::iequals(r->GetHeader("Connection"), "Close"));

    // Close by using request builder.
    r = session.Send(webcc::RequestBuilder{}.Get(url).KeepAlive(false)());

    EXPECT_TRUE(boost::iequals(r->GetHeader("Connection"), "Close"));

    // Keep-Alive explicitly by using request builder.
    r = session.Send(webcc::RequestBuilder{}.Get(url).KeepAlive(true)());

    EXPECT_TRUE(boost::iequals(r->GetHeader("Connection"), "Keep-Alive"));

  } catch (const webcc::Error& error) {
    std::cerr << error << std::endl;
  }
}

// Test that URL scheme is NOT case sensitive.
TEST(ClientTest, UpperCaseUrlScheme) {
  webcc::ClientSession session;

  try {
    auto r = session.Send(WEBCC_GET("HTTP://httpbin.org/get")());

    EXPECT_EQ(webcc::Status::kOK, r->status());

  } catch (const webcc::Error& error) {
    std::cerr << error << std::endl;
  }
}

TEST(ClientTest, InvalidUrlScheme) {
  webcc::ClientSession session;

  webcc::Error::Code error_code = webcc::Error::kUnknownError;

  try {
    // NOTE: "httb" is not a valid/supported scheme.
    auto r = session.Send(WEBCC_GET("httb://httpbin.org/get")());

  } catch (const webcc::Error& error) {
    error_code = error.code();
  }

  EXPECT_EQ(webcc::Error::kSyntaxError, error_code);
}